1. Field
The present disclosure relates to a system and method for data transmission system between an intelligent electronic device (IED) and a remote display or input/output (I/O) device. In particular, the present disclosure relates to a system and method for data transmission between an IED and a remote display or I/O device that minimizes the number of digital lines needed for a large number of data channels. In addition, the present disclosure provides for the use of a fiber optic medium for the data transmission thereby providing for a fast transmission system and method which is intrinsically isolated and electrically non-conductive.
2. Description of the Related Art
Electric utility companies (“utilities”) track electric usage by customers by using power meters. These meters track the amount of power consumed at a particular location. These locations range from power substations, to commercial businesses, to residential homes. The electric utility companies use information obtained from the power meter to charge their customers for their power consumption, i.e., revenue metering.
A popular type of power meter is the socket-type power meter, i.e., S-base or Type S meter. As its name implies, the meter itself plugs into a socket for easy installation, removal and replacement. Other meter installations include panel mounted, switchboard mounted, and circuit breaker mounted. Typically, the power meter connects between utility power lines supplying electricity and a usage point, namely, a residence or commercial place of business.
A power meter may also be placed at a point within the utility's power grid to monitor power flowing through that point for distribution, power loss, or capacity monitoring, e.g., at a substation. These power and energy meters are installed in substations to provide a visual display of real-time data and to alarm when problems occur. These problems include limit alarms, breaker control, outages and many other types of events.
Intelligent electronic display devices provide valuable data for display and for processing by other equipment, e.g., another IED, a head end of a SCADA system, computing device, etc. There are typically multiple data lines to be transmitted from perhaps an IED to a display (or another device) at a remote location. Multiple data lines can be extremely costly to install, e.g., depending on a number of lines (i.e., multi-conductor cables) to be run and the size of a raceway (i.e., metal conduit) to hide or protect the multi-conductor cables. Further, transmission of this data by a high speed medium such as fiber optics requires a separate line for each data line and this would prove costly.
For example, FIGS. 1A-C illustrate a typical socket-type power meter. An exemplary socket meter is described in commonly owned U.S. patent application Ser. No. 12/578,062, the contents of which are hereby incorporated by reference in its entirety. The meter includes a main housing 12 surrounded by a cover 14. The cover 14 is preferably made of a clear material to expose a display 16 disposed on the main body 12. An interface 18 to access the display and a communication port 20 is also provided and accessible through the cover 14. The meter 10 further includes a plurality of current terminals 22 and voltage terminals 24 disposed on backside of the meter. The terminals 22, 24 are designed to mate with matching jaws of a detachable meter-mounting device, such as a revenue meter socket. The socket is hard wired to the electrical circuit and is not meant to be removed. To install an S-base meter, the utility need only plug in the meter into the socket. Once installed, a socket-sealing ring 26 is used as a seal between the meter 10 and/or cover 14 and the meter socket to prevent removal of the meter and to indicate tampering with the meter. However, installation of the meter 10 is complicated by the plurality cable extending through the rear side of the meter as shown in FIG. 1C.
In the configuration shown, at least seven cables for communications and remote signaling leave the rear side of the meter 10. This bundle of cables slows the installation process since great care must taken not to pinch any of the cable as the meter is mated to the socket. Furthermore, the installer must ensure the bundle of cables is separated from any high voltage, which may effect the signals being transmitted over the bundle.
Therefore, a need exists for a high speed data transmission system and method for transmitting data from an IED to a remote display, another IED, input/output devices (I/O), computing devices and the like. Furthermore, a need exists for such a system and method to utilize less external wiring which will result in lower manufacturing costs and reduced installation time and costs.